Common Challenges in Concrete Joint Installation and How to Overcome Them

Con­crete joint instal­la­tion comes with chal­lenges. This arti­cle will dis­cuss these issues and pro­vide prac­ti­cal solu­tions to over­come them effectively.

Impor­tance of Prop­er­ly Installed Con­crete Joints

Con­crete seems to be the per­fect con­struc­tion mate­r­i­al, with its incred­i­ble strength, dura­bil­i­ty, and longevi­ty. It’s also resis­tant to var­i­ous envi­ron­men­tal fac­tors, ener­gy effi­cient due to its heat-reflect­ing prop­er­ties, and requires min­i­mal main­te­nance. Fur­ther­more, it doesn’t rot or get infest­ed by termites.

How­ev­er, con­crete also has a weak­ness: it has rel­a­tive­ly low ten­sile strength. So, cracks occur when ten­sile forces exceed the concrete’s strength. Cracks are not only unsight­ly but can also be dan­ger­ous. They can com­pro­mise the struc­tur­al integri­ty of con­crete and the sur­round­ing struc­tures. Addi­tion­al­ly, cracks can be a safe­ty risk.

Cracks are inevitable in con­crete. That’s why con­trac­tors install joints to pre­vent these cracks from occur­ring in ran­dom places. Con­crete joints allow the con­crete to crack in a con­trolled man­ner when exposed to tem­per­a­ture changes, dry­ing shrink­ages, and mois­ture variations. 

Giv­en the vital role of joints, installing them right is crucial.

Com­mon Chal­lenges in Con­crete Joint Installation

When you look at a new­ly poured con­crete floor, you’ll notice tiny gaps. These are the joints. A con­crete joint is a pur­pose­ful divi­sion or break in a con­crete struc­ture designed to con­trol the extent and loca­tion of crack­ing that occurs as con­crete cures and shrinks. They may seem easy to install at first glance. In real­i­ty, many mis­takes can be made in design­ing and installing these joints, result­ing in exten­sive con­crete crack­ing with­in a few days, weeks, or months after the installation.

Fix­ing fail­ures in con­crete joint instal­la­tion can be cost­ly, espe­cial­ly in a busy facil­i­ty, so it’s impor­tant to do it right the first time. As a facil­i­ty man­ag­er or own­er, you can avoid the cost­ly con­se­quences of improp­er­ly installing joints by being aware of the com­mon mis­takes or chal­lenges in con­crete joint installation.

Incor­rect Joint Spac­ing and Depth

Incor­rect joint spac­ing or depth is one rea­son con­crete struc­tures still crack despite hav­ing joints. So, it’s cru­cial to deter­mine the right spac­ing and depth and learn how to install con­crete expan­sion joints.

Get­ting the spac­ing and depth right may be a bit tricky because dif­fer­ent joints have dif­fer­ent require­ments. Gen­er­al­ly, con­crete joints come in three types: con­struc­tion, con­trac­tion (or ​“con­trol”), and con­crete expan­sion joints.

Con­struc­tion joints serve as the start and end points when pour­ing con­crete. Prop­er spac­ing and depth are nec­es­sary when the con­struc­tion joints have to func­tion as con­trac­tion joints.

The max­i­mum spac­ing in feet between these joints is two to three times the slab thick­ness in inch­es. This is the gen­er­al­ly rec­om­mend­ed prac­tice, but the spac­ing varies depend­ing on the con­crete mix, slab thick­ness, and tem­per­a­ture, among oth­er things. In terms of depth, con­trac­tors should cut joints 25% of the depth of the con­crete slab. How­ev­er, like spac­ing, many fac­tors should be con­sid­ered when deter­min­ing the depth, includ­ing joint design, saw type, etc.

As a facil­i­ty man­ag­er or own­er, you can require your con­trac­tor to sub­mit a joint spac­ing plan that you can review to ensure every­thing is right. You can review the ACI guide­lines for joint spac­ing as a reference.

Fail­ure to Use Prop­er Joint Fillers and Sealants

Joint fillers and sealants pro­tect con­trol and expan­sion joints in con­crete and make the floor more appealing. 

These fillers and sealants can be made of var­i­ous mate­ri­als. The num­ber of options can be a dou­ble-edged sword because an inex­pe­ri­enced con­trac­tor may select the wrong one. Using the wrong mate­r­i­al can sig­nif­i­cant­ly impact the per­for­mance of the con­crete and lead to ear­ly joint failure.

Here are some con­crete joint filler options:

• Bitu­mi­nous Fiber­board: This filler com­bines bitu­men, also known as asphalt, and wood fibers, boast­ing excel­lent mem­o­ry prop­er­ties and flexibility.

• Foam Backer Rods: These are dense, closed-cell, foam-like pool noo­dles, except they’re spe­cial­ly designed for con­struc­tion. They pack tight­ly into any joint.

• Poly­eth­yl­ene Filler Board: Made of poly­eth­yl­ene, this filler is semi-rigid, non-absorbent, and UV-resis­tant. It’s com­mon­ly used in high­ways, bridges, run­ways, and reservoirs.

• Resin Bond­ed Cork Filler. This option com­bines ground cord and syn­thet­ic resin, mak­ing it eco­nom­i­cal and flexible.

The right con­crete joint filler and sealant will vary depend­ing on numer­ous fac­tors, includ­ing joint type and expect­ed joint move­ments, cli­mate, and bond com­pat­i­bil­i­ty with sub­strate mate­ri­als. Hence, the per­son choos­ing these mate­ri­als must be knowl­edge­able enough to ensure the cho­sen mate­r­i­al meets the requirements.

Envi­ron­men­tal Fac­tors: Tem­per­a­ture, Mois­ture, and Chem­i­cal Exposure

Envi­ron­men­tal fac­tors can also make joint instal­la­tion chal­leng­ing. Installing the joints under the wrong con­di­tions will result in cracks and oth­er prob­lems that could com­pro­mise the entire project. For exam­ple, joint filler applied when the tem­per­a­ture is too low will not reach a com­plete cure and achieve the intend­ed phys­i­cal prop­er­ties, caus­ing pre­ma­ture failure. 

Anoth­er exam­ple is wait­ing too long to cut con­trol joints dur­ing hot weath­er. A con­crete mix sets much quick­er dur­ing hot weath­er, so there will be much less time to place the joints cor­rect­ly. If you wait for even just six hours before cut­ting joints, cracks may occur.

For­tu­nate­ly, over­com­ing this chal­lenge isn’t much of a prob­lem. With enough prepa­ra­tion, envi­ron­men­tal fac­tors, includ­ing tem­per­a­ture and mois­ture, are less like­ly to become a problem.

Keep Con­crete Joints Func­tion­al With Reg­u­lar Main­te­nance and Time­ly Repair

Cre­at­ing the right gaps at the right spac­ing and depth and fill­ing them with the cor­rect filler and sealant are all vital to pro­tect­ing the integri­ty of your con­crete slab. How­ev­er, even a prop­er­ly installed con­crete joint even­tu­al­ly gets dam­aged over time. Reg­u­lar main­te­nance is nec­es­sary to keep con­crete joints func­tion­al and max­i­mize their ser­vice life.

Keep dirt and debris out of the joint. If water spills or accu­mu­lates on top of joints, remove it imme­di­ate­ly so it doesn’t pen­e­trate the joints. Stand­ing water may infil­trate the con­crete, caus­ing more dam­age. Also, don’t ignore any con­crete joint repair. Take a clos­er look to deter­mine what the defects of the con­crete joints are and imme­di­ate­ly call your trust­ed con­trac­tor to fix a dam­aged joint. It’s best to repair the dam­age while it’s minor rather than wait for it to spi­ral out of control.

Dam­aged con­crete joints com­pro­mise the integri­ty of the struc­ture. Dete­ri­o­rat­ed joints can also affect pro­duc­tiv­i­ty in a facil­i­ty, as vehi­cle oper­a­tors slow down when they approach the joints. Vehi­cle wheels will like­ly get dam­aged, result­ing in down­time, expen­sive wheel replace­ment, and wast­ed per­son­nel time. In short, dam­aged con­crete joints can lead to the loss of valu­able time for oper­a­tions and exces­sive expenses.

Con­tact Kaloutas for Pro­fes­sion­al Con­crete Joint Repair

The impor­tance of prop­er con­crete joint instal­la­tion can­not be over­stat­ed. Com­mon mis­takes in joint instal­la­tion can result in pre­ma­ture con­crete crack­ing and many oth­er issues. Address these mis­takes imme­di­ate­ly to pre­vent them from get­ting worse. Con­tact your trust­ed local con­trac­tor for pro­fes­sion­al con­crete joint repair.

If your facil­i­ty is based in New Eng­land, you can count on Kaloutas to repair dam­aged joints in con­crete floor­ing. If you just had your con­crete floor installed, our team can cut a new joint and fill it with the right filler. We can also repair and replace the epoxy coat­ing on the sur­round­ing floor to ensure that it remains safe, attrac­tive, and durable for years.

Talk to a Kaloutas floor­ing pro­fes­sion­al for more infor­ma­tion on con­crete joint main­te­nance and repair.